Apoptosis in human endometrium and endometriosis

Abstract

Apoptosis plays a critical role in maintaining tissue homeostasis and represents a normal function to eliminate excess or dysfunctional cells. Accumulated evidence suggests that apoptosis helps to maintain cellular homeostasis during the menstrual cycle by eliminating senescent cells from the functional layer of the uterine endometrium during the late secretory and menstrual phase of the cycle. The BCL-2 family and Fas/FasL system have been extensively studied in human endometrium and endometriotic tissues. Eutopic endometrium from women with endometriosis reportedly has some fundamental differences compared with normal endometrium of women without endometriosis. The differences could contribute to the survival of regurgitating endometrial cells into the peritoneal cavity and the development of endometriosis. One mechanism that recently gained a lot of interest is the finding that apoptosis appeared in eutopic and ectopic endometrium of patients with endometriosis. This study is a current review of the literature focused on the physiological role of apoptosis in normal endometrium and the alterations in regulation of apoptosis in eutopic and ectopic endometrium from women with endometriosis. Similarities in characteristics of endometriosis at a molecular level with gynaecological tumours are also discussed. Finally, the role of apoptosis in the treatment of endometriosis is reviewed to link the basic research findings into clinical applications.

Endometrium from women with endometriosis shows increased proliferation activity

“…However, it is not yet known whether these processes are primary factors in endometriosis or are a secondary phenomenon (16). Physiologically, refluxed endometrial tissue during menstruation undergoes apoptosis because it does not normally interact with extracellular stromal tissues or react with receptors (17).…”

The Local Immune Mechanisms Involved in the Formation of Endometriotic Lesions

“…The suggestion that the primary defect in endometriosis is located in the eutopic endometrium, was proposed many years ago and supported now by many investigators (Vinatier et al, 2001;Kyama et al, 2003;Harada et al, 2004), though the eutopic endometrium of women with and without endometriosis is histologically similar. This hypothesis is confirmed by different studies revealing that there are many fundamental differences between these two tissues.…”

“…The most widely accepted Sampson's transplantation theory proposes that, during menstruation, there is reflux of endometrial tissue via fallopian tubes into abdominal cavity where endometrium could attach to peritoneal surfaces, proliferate, invade, and become the disease known as endometriosis. However, this theory does not account for the fact that most of women of reproductive age exhibit some degree of reflux of endometrial debris, but only some patients develop endometriosis (Harada et al, 2004;Vinatier et al, 2001). There are two main suggestions explaining this contradiction.…”

Le devenir des cellules SDF

“…La survie des cellules endométriales présentes dans la cavité périto- néale au cours de rétromenstruations pourrait être un élément-clé dans le déve-loppement de l'endométriose [10]. De plus, tous les éléments qui favorisent la survie des cellules détachées et leur adhé-rence sur un nouveau substrat pourraient être propices à la dissémination et à la prolifération des cellules cancéreuses.…”